Gastroparesis Patients and Healthy Controls ages 20-49 will be asked to participate in an observational study measuring vagal activity following food ingestion in order to establish parameters of autonomic nerve/vagal function in healthy human subjects compared to those with gastroparesis. Information generated from this study may be used in the future to establish what is normal and abnormal enteric vagal tone and how much vagal nerve stimulation treatment may be required to help patients with gastroparesis.
This study is investigating a new form of treatment for a digestive disorder called gastroparesis. Gastroparesis is thought to be caused by a mix of inflammation and neural dysfunction. The vagal nerve is a large nerve originating from the brain that regulates digestive function. Patients with gastroparesis have what is a called a low vagal tone which results in gastrointestinal motility problems and inflammation; therefore, investigators hypothesize that increasing vagal tone through a hand-held vagal nerve simulator will reduce inflammation and gastrointestinal motility problems in gastroparesis patients. Investigators will evaluate this hypothesis through the use of upper endoscopy testing, breath testing, and blood, stool, urine, heart rate variability, and saliva testing before and after 4 weeks of vagal nerve stimulation (VNS) treatment. There are 6 research visits Visit 1 and visit 2 may take up to 8 weeks (screening/baseline) Visit 3 and visit 4 will take 4 weeks (VNS treatment) visit 5 and 6 will take approximately 4 weeks (VNS followup/washout) Consequently, it is possible that if a patient were to be at the farthest ends of visit windows, they could potentially be in the study for approx 16 weeks. Visit 1 and 2 may be less than 8 weeks which would shorten the patient's overall involvement in the study. The treatment phase of the study will always be 4 weeks with an additional 4 week washout phase. Use of the VNS device takes 4 weeks. Endoscopy and blood work are taken before and after the treatment period.
BACKGROUND: Gastroparesis, a chronic motility disorder characterized by delayed gastric emptying, abdominal pain, nausea, and vomiting, remains largely unexplained. Medical therapy is limited, reflecting the complex physiology of gastric sensorimotor function. Vagus nerve stimulation is an attractive therapeutic modality for gastroparesis, but prior methods required invasive surgery. In this open-label pilot study, we aimed to assess the benefit of non-invasive vagal nerve stimulation in patients with mild to moderate idiopathic gastroparesis.METHODS: Patients self-administered the gammaCore vagal nerve stimulator for 4weeks. The gastroparesis cardinal symptom index daily diary (GCSI-dd) was assessed during a two-week run-in period, ?4weeks of therapy, and 4weeks after therapy was completed. Gastric emptying and autonomic function testing were also performed. The primary endpoint was an absolute reduction in CGSI-dd of 0.75 after nVNS.RESULTS: There was a total improvement in symptom scores (2.56±0.76 to 1.87±1.05; P=.01), with 6/15 (40%) participants meeting our primary endpoint. Therapy was associated with a reduction in gastric emptying (T1/2 155 vs 129minutes; P=.053, CI -0.4 to 45). Therapy did not correct autonomic function abnormalities, but was associated with modulation of reflex parasympathetic activity.CONCLUSIONS: Short-term non-invasive vagal nerve stimulation led to improved cardinal symptoms and accelerated gastric emptying in a subset of patients with idiopathic gastroparesis. Responders had more severe gastric delay at baseline and clinical improvement correlated with duration of therapy, but not with improvements in gastric emptying. Larger randomized sham-controlled trials of greater duration are needed to confirm the results of this pilot study.
View details for DOI 10.1111/nmo.13769
View details for PubMedID 31802596
